Petroleum lubricant product



Patented Apr. 4, 1939 UNITED STATES PETROLEUM LUBRICANT raonuc'r Henry G. Berger, Woodbury, Robert G. Moran, Wenonah, and Francis M. Seger, Woodbury, N. J., assignors to Socony-Vacuum Oil Company, Incorporated, New York, N. poration of New York Y., a cor- No Drawing. Application February 3, 1937,

Serial N0. 123,846 1 2 Claims.

v This invention is specifically directed to petroleum lubricant products capable of maintaining lubricant -films under conditions of extremely high unit pressure, known as E. P. (extreme pressure) lubricants.

The lubrication of machine parts, such as for example the hypoid gears used in automotive power transmission, wherein high unit pressures are combined with high rubbing speeds is beyond the capabilities of ordinary mineral lubricants alone. It is common practice to produce extreme pressure lubricants by the addition to mineral oils of such substances as free sulphur, chemically bound sulphur as found in sulphurized fatty oil, chlorinated aromatic hydrocarbons with or without fatty oils, esters of various acids of phosphorus, as well as combinations of some of the above, or combinations of metallic soaps and sulphurized oils. Some of these materials are not suitable where pressures are in excess of 2,000

pounds per square inch and thus are not satisfactory for heavy duty such as in hypoid gears on buses and trucks. Some have a pronounced tendency to form sludge on standing or in service, some have too short a' life span to permit of commercial use, and some separate in service or storage to form products highly corrosive to con tainers and equipment to be lubricated.

The object of this invention is to provide extreme pressure lubricants containing a novel and efl'ective characterizing ingredient which gives high lubricating power, is stable in service and storage, and which is not highly corrosive to the materials in contact with which it is stored and used.

This invention is based upon the discovery that these objects may be attained by blendingwith mineral oils a substance obtained by the reaction of chlorinated hydrocarbons which are largely aliphatic in nature with potassium ethyl xanthate.

Chlorinated aromatic materials such as chlorinated naphthalene and chlorinated diphenyl have been used as E. P. ingredients. These materials are too high in stability to readily yield chlorine under conditions of use and alone are ineffective for the higher levels of pressure. Chlorinated aliphatic materials are too unstable, and while highly effective as E. P. ingredients decompose readily to products corrosive to containers and equipment lubricated and so are not commercially usable.

This invention is based upon the discovery that chlorinated aliphatic compounds may be reacted pared by chlorlnating petroleum napntna until it contained about 54% by weight of chlorine. Two hundred parts of this were dissolved in about 500 parts of acetone, and placed in a reaction vessel heated by a water jacket and equipped with stirrer and reflux condenser. Then parts of potassium xanthate were added, .and the mixture held at the boiling temperature, with stirring, under reflux, .for about 2 hours. The resulting mixture was cooled to roomv temperature, filtered, and the filtrate subjected to distillation to remove the acetone. After removal of acetone, the product was washed to remove potassium salts, dried, and filtered. The finished reaction product was a dark brown liquid, containing about 12% of sulphur and37% of chlorine. Then 254 parts of product were recovered. Variation in sulphur and chlorine content can be obtained by varying the degree of chlorination of I the naphtha and by varying the amount of potassium xanthate used, to give a group of xanthochlornaphthas of wide varying compositions- The nature of the light aliphatic hydrocarbon may 'manner the usual evaluation test used in the art. Actual gear tests show such blends to have good extreme pressure properties without any tendency to form sludge. These blends are not corrosive towardsteel, although they will corrode copper under long exposure at high temperature.

To show the efllcacy of these oils, the following tests are noted, wherein a blend of mineral oil of -160 Saybolt Universal viscosity at 210 F. and 10% of 'xanthochlornaphtha was subjected to test-in the Almen Pin Test, described by Wolf and Mougey, Proc. A. P. I. 1932, pp. 118- 130, and the S. A. E. test described Annon S. A. E. Journal 39, 29-4 (1936), with the following results:

S. A. E. testload limit, lbs. Almen test load limit,

R. P. M. R. P. M.

30 000+. 580+ 47o 3o1ooo+ 430 I In actual test with a hypoid .gear loaded at 3500 pounds per linear inch of tooth, built up from 0 pounds in 35 seconds and held for two hours, only very slight scratches appeared upon the gear faces. Most other so-called E. P. lubricants, including the 'lead soap-sulphur compounds, score the gears badly under the same test.

These xanthochlornaphthas may be used for the purposes of 'this invention in concentration of from 1 to 20% of the mixture. It is preferred to use about 10%.

We claim: I

1. A lubricant product for use where high un pressures are combined with high rubbing speeds comprising a major portion of mineral lubricat- 15 ing oil and a minor portion of the reaction product secured by reacting chlorinated petroleum naphtha-.with.potassium ethyl xanthate, said reaction product containing sulfur in the form.

CERTIFICATE OF CORRECTION.

Patent No 2, 53 $.95

It is hereby certified April by 959 ENRY G. BERGER ET AL.

that error appears in the printed specification of the above numbered patent requiring correction as follows:

Page i second column, line 1+7, for "29-h" read 25-11,; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 6th day of June, A. Do 1959:

(Seal) Henry Van Arsdale Acting Co nmissioner of Patents. 

